VI) Title: Shaping the Earth through Chemical Weathering
Summary:The students will make connections between the antacid lab they are completeing in class today and the information learned about mechanical weathering during class last period. We will discuss the affects of chemical weathering and the processes of chemical weathering which they took notes on during their homework. Through experiments the students will be able to visually see the effects of chemical and mechanical weathering. They will make connections between the two types of weathering by examining how they facilitate one another. The students will write a formal lab report along for this lab.
Objectives:
Students will be able to describe the processes of chemical weathering.
Students will examine mechanical and chemical weathering through the antacid experiment.
Students will be able to compare and contrast mechanical and chemical weathering.
Students will examine chemical and mechanical weathering through the antacid lab and will draw conclusions about both from their results.
take one antacid tab and drop it into a beaker of water.
As it dissolves ask the students what type of weathering they think is being simulated by this demonstration, chemical or mechanical.
explain that the antacid is similar to the process of carbonate rocks being dissolved by carbonic acid which is the combination of water and carbon dioxide in the air.
Indicate to the students that they can use the information they learned about mechanical weathering to make some inferences about what kind of weathering is occuring.
Discuss with the characteristics of chemical weathering that they learned navigating the web site for homework
Have the students compare and contrast mechanical and chemical weathering
Middle
Instruct the students to gather themselves into groups of 4 or 5.
Then explain that the lab they will be doing today will involve investigating chemical weathering and will compare it with mechanical weathering.
Explain that an important variable they will be testing is temperature. They will be exploring the effects of temperature on chemical weathering
Review the procedure and materials that will be needed for each group.
Instruct the students to write a purpose and hypothesis for the lab.
Have the students begin the lab following the procedure that was handed out and discussed.
First, put hot tap water into 1000mL beaker add ice and measure the temperature. Once the temperature has reached 50 degrees Celsius remove the ice and record the temperature.
drop an antacid tablet into the water, time with the stop watch how long it takes for the antacid to dissolve. record the time. and the final temperature of the water when the antacid has dissolved.
pour out the water in the 1000mL beaker and pour hot tap water into it again. This time add ice and let the temperature lower until it reaches about 40 degrees Celsius. Remove the ice and put an antacid tablet into the water. Use the stop watch to measure the time it takes to dissolve and record the time.
repeat the previous step for a container of water that is 30 degrees Celsius and 20 degrees Celsius. record your results.
Instruct the students to write their data on the board ( in a table that is already set up) explain that they will be taking a class average of all of the groups data.
Instruct them to record the class averages in their notes and explain that the class averages should be included in their final data table and should be used for their graph.
Ask the students why it is important for the average to be used instead of the individual data they recorded within their groups
Closing
Instruct the students to pick up the lab materials they used except for a small amount of water and one antacid tablet each.
Have the students use their fingertips to collect a drop or two of water and place it on the antacid tablet in their hands.
Then instruct the students to use their fingers to crush break apart the antacid tablet.
Ask the students what they think is happening reference to weathering.
Explain that chemical weathering can facilitate mechanical weathering and vice versa.
Remind the students that for homework they need to complete a formal lab report which will include a hypothesis, purpose, procedure, data section and a conclusion which analyses their results and provides sources of error.
Notes:
The lab and materials need to be set up ahead of time, plan for about 10 minutes of prep time.
Students will have learned and taken notes about graphing previous to this lab as well as the format for a formal laboratory report. an outline of the structure of a lab report is already given to all students for them to staple into their notebooks and are available to be used for reference.
Accomidations:
Students whom need organizational supports will be given a guided organizer to aid in writing their lab report and gathering data
Title: Shaping the Earth through Chemical Weathering
Summary:The students will make connections between the antacid lab they are completeing in class today and the information learned about mechanical weathering during class last period. We will discuss the affects of chemical weathering and the processes of chemical weathering which they took notes on during their homework. Through experiments the students will be able to visually see the effects of chemical and mechanical weathering. They will make connections between the two types of weathering by examining how they facilitate one another. The students will write a formal lab report along for this lab.
Objectives:
Materials:
Instruction:
Opening
Middle
Closing
Notes:
Accomidations: